Exploring alternative semiconductor materials and device geometries for topological quantum devices*

For more than a decade, searches for topological superconductivity in quantum devices have largely focused on InSb and InAs nanowires, due to their combination of large spin-orbit coupling and one dimensional transport. However, alternative device morphologies, geometries, and even material platforms exist which maintain these key properties while expanding the scope and capability of possible devices and experiments. As an example, InSb nanoribbons break the typical hexagonal symmetry of nanowires and thus introduce a highly anisotropic magnetic field response while maintaining robust 1D transport. High quality PbTe selective-area-growth nanowire networks maintain strong spin-orbit coupling but move away from the conventional III-V wire approach, realizing zero-field quantized conductance with extremely flexible device geometry. We present progress from our ongoing work on these alternative platforms, and discuss future directions and opportunities.